Rolls-Royce Vulture

Rolls-Royce's Vulture was an X-24 aircraft engine of the World War II era. Originally designed to produce around 1,750 hp, continuing problems with both the Vulture and the underlying Peregrine meant that they were derated to around 1,450-1,550 hp in service. Although several aircraft designs had planned on using the Vulture, work on the design ended in 1941 as Rolls concentrated on their more successful Merlin. Another engine produced to the same criteria, the Napier Sabre, would prove more successful after a lengthy shaking-out period.

Design and development

The Peregrine, a supercharged Kestrel, was a fairly standard design (at first sight) with two cylinder banks arranged in a V form and with a displacement of 22 litres. The Vulture was basically two Peregrines joined at the crankcase, producing an X engine configuration with a displacement of 44 litres.

Both engines suffered from a far too short pre-service development period and the reliability was very poor. Apart from delivering significantly less than the designed power, the Vulture suffered from frequent failures of the big-end connecting-rod bearings, which was found to be caused by a breakdown in lubrication, and also from other engine heat dissipation problems. Rolls-Royce were initially confident that they could solve the problems, however the company's much smaller Merlin had already reached the same power level as the Vulture's original specification, and so production of the Vulture was discontinued after only 538 had been built. [Lumsden 2003, p.200.]

Applications

The Vulture had been intended to go into the Hawker Tornado, but with the cancellation of Vulture development, Hawker abandoned the Tornado and concentrated on the Hawker Typhoon, which was powered by the Napier Sabre. Likewise, the same cancellation caused the abandonment of the Vulture-engined version of the Vickers Warwick bomber.

The only aircraft type designed for the Vulture to actually go into production was the twin-engined Avro Manchester. When the engine reliability issues became clear, the Avro team (who were designing a four-Merlin version as a contingency plan) persuaded the Air Ministry that switching to the four-Merlin version of the Manchester was preferable to retooling Avro's factories to make Handley Page Halifaxes. The resulting aircraft was initially called the Manchester Mark III and then renamed Lancaster, going on to great success as the RAF's leading heavy bomber.

pecifications (Vulture V)

"Data from:" Lumsden [Lumsden 2003, p.201.] pistonspecs

type=24-cylinder supercharged liquid-cooled 90 degree X layout aircraft piston engine
bore=5 inches (127 mm)
stroke=5.5 inches (140 mm)
displacement=2,591.8 in³ (42.47 L)
length=
diameter=
width=
height=
weight=
valvetrain=Overhead camshaft
supercharger=Gear-driven centrifugal type supercharger, two speed
turbocharger=
fuelsystem=Downdraught S.U. carburettor
fueltype=Petrol
oilsystem=
coolingsystem=Liquid cooled, 70% water/30% Ethylene glycol
power=1780 hp at 2,850 rpm, +6 psi boost (bmep = 190.9psi)
specpower=
compression=6:1
fuelcon=
specfuelcon=
oilcon=
power/weight=

ee also

*List of aircraft engines

References

Notes

Bibliography

* Lumsden, Alec. "British Piston Engines and their Aircraft". Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.

External links

* [http://www.mapica.org/modules/epave/ Recovered Manchester and Vultures (in French)]
* [http://www.stobbe.dk/library/engines/rolls_royce/images/RR-Vulture.jpgPhoto of a Rolls-Royce Vulture]